I haven't quite got it working yet, but yes I have identified that on the UK TiVos the input chip is the Phillips SAA7118E. I have found the datasheet and I believe I have identified the correct register to flip it from S-Video to RGB (02H). I think I have also identified the subregister of the chip (0x42). I just haven't quite worked out how to form the command using iicsetw just yet, in particular how to make it address 0x42, but I've only just started looking at that code and ran out of time. I also wonder that when I flip the mode that there might need to be other registers poked as well, but I guess that will come down to some testing.

I guess its very similar to the component output mod, except that I looking to adjust the input chip too. What I did notice while looing at the 7118 datasheet was that the chip does Component *input* as well as RGB input. I'm thinking that after I figure out how to get both RGB input and output going, I might try getting both Component input and output going. Given that every modern TV now supports Component in Australia I feel that this will be quite useful to other people. (Certainly on my HD TVs there is a noticable difference from S-Video to Component, which is why I purchased UK TiVos in the first place. I'm sure there would be others who feel the same way.)